This 1995 Chevrolet Caprice came in with the complaint that the engine would stall if the headlights were turned on or if the brake pedal was depressed. The problem was also intermittent. The strange thing was that it would feel like the engine was running out of fuel rather than just an instant turn off. I did a little research into the problem and found a reference to a shared ground at the left side of the trunk.
After locating and inspecting the shared ground I found that it was loose and was definitely the cause of the problem. I cleaned and tightened the connections and the issue was resolved.
To clarify the grounds at this location were for the rear lights and the fuel pump. Also not seen in the above image is the large speaker enclosure that would move around in the trunk and had bumped into the wiring causing the screw to loosen.